Check that negative constants are printed properly in emitc (#7028)

iree/compiler/Dialect/VM/Target/C/test/constant_ops.mlir

diff --git a/iree/compiler/Dialect/VM/Target/C/test/constant_ops.mlir b/iree/compiler/Dialect/VM/Target/C/test/constant_ops.mlir
index 341ef9c..8d5ee0c 100644
--- a/iree/compiler/Dialect/VM/Target/C/test/constant_ops.mlir
+++ b/iree/compiler/Dialect/VM/Target/C/test/constant_ops.mlir
@@ -1,13 +1,13 @@
-// RUN: iree-translate -iree-vm-ir-to-c-module -iree-vm-c-module-optimize=false %s | IreeFileCheck %s
+// RUN: iree-translate -split-input-file -iree-vm-ir-to-c-module -iree-vm-c-module-optimize=false %s | IreeFileCheck %s
 
-vm.module @constant_ops {
+vm.module @rodata_ops {
   // Check the generated arrays
 
-  // CHECK: iree_alignas(16) static const uint8_t constant_ops_buffer_1[] = {1, 2, 3};
-  // CHECK-NEXT: iree_alignas(16) static const uint8_t constant_ops_buffer_2[] = {1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0};
+  // CHECK: iree_alignas(16) static const uint8_t rodata_ops_buffer_1[] = {1, 2, 3};
+  // CHECK-NEXT: iree_alignas(16) static const uint8_t rodata_ops_buffer_2[] = {1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0};
 
   // Check the generated state struct
-  // CHECK-LABEL: struct constant_ops_state_t {
+  // CHECK-LABEL: struct rodata_ops_state_t {
   // CHECK-NEXT: iree_allocator_t allocator;
   // CHECK-NEXT: uint8_t rwdata[1];
   // CHECK-NEXT: iree_vm_ref_t refs[1];
@@ -21,22 +21,35 @@
   vm.rodata public @buffer_2 dense<[1, 2, 3]> : tensor<3xi32>
 
   // check state initialization inside the alloc_state function
-  // CHECK-LABEL: static iree_status_t constant_ops_alloc_state(
+  // CHECK-LABEL: static iree_status_t rodata_ops_alloc_state(
   // CHECK: [[STATE:[^ ]*]] = NULL;
   
-  // CHECK: [[VOID_PTR_1:[^ ]*]] = EMITC_CAST(constant_ops_buffer_1, void*);
-  // CHECK-NEXT: [[SIZE_1:[^ ]*]] = sizeof(constant_ops_buffer_1);
+  // CHECK: [[VOID_PTR_1:[^ ]*]] = EMITC_CAST(rodata_ops_buffer_1, void*);
+  // CHECK-NEXT: [[SIZE_1:[^ ]*]] = sizeof(rodata_ops_buffer_1);
   // CHECK-NEXT: [[BYTE_SPAN_1:[^ ]*]] = iree_make_byte_span([[VOID_PTR_1]], [[SIZE_1]]);
   // CHECK-NEXT: [[ALLOCATOR_1:[^ ]*]] = iree_allocator_null();
   // CHECK-NEXT: [[BUFFERS_1:[^ ]*]] = EMITC_STRUCT_PTR_MEMBER([[STATE]], rodata_buffers);
   // CHECK-NEXT: [[BUFFER_1:[^ ]*]] = EMITC_ARRAY_ELEMENT_ADDRESS([[BUFFERS_1]], 0);
   // CHECK-NEXT: iree_vm_buffer_initialize(IREE_VM_BUFFER_ACCESS_ORIGIN_MODULE, [[BYTE_SPAN_1]], [[ALLOCATOR_1]], [[BUFFER_1]]);
 
-  // CHECK: [[VOID_PTR_2:[^ ]*]] = EMITC_CAST(constant_ops_buffer_2, void*);
-  // CHECK-NEXT: [[SIZE_2:[^ ]*]] = sizeof(constant_ops_buffer_2);
+  // CHECK: [[VOID_PTR_2:[^ ]*]] = EMITC_CAST(rodata_ops_buffer_2, void*);
+  // CHECK-NEXT: [[SIZE_2:[^ ]*]] = sizeof(rodata_ops_buffer_2);
   // CHECK-NEXT: [[BYTE_SPAN_2:[^ ]*]] = iree_make_byte_span([[VOID_PTR_2]], [[SIZE_2]]);
   // CHECK-NEXT: [[ALLOCATOR_2:[^ ]*]] = iree_allocator_null();
   // CHECK-NEXT: [[BUFFERS_2:[^ ]*]] = EMITC_STRUCT_PTR_MEMBER([[STATE]], rodata_buffers);
   // CHECK-NEXT: [[BUFFER_2:[^ ]*]] = EMITC_ARRAY_ELEMENT_ADDRESS([[BUFFERS_2]], 1);
   // CHECK-NEXT: iree_vm_buffer_initialize(IREE_VM_BUFFER_ACCESS_ORIGIN_MODULE, [[BYTE_SPAN_2]], [[ALLOCATOR_2]], [[BUFFER_2]]);
 }
+
+// -----
+
+vm.module @constant_ops {
+  // CHECK-LABEL: constant_ops_neg_constant
+  vm.func @neg_constant() -> i32 {
+    // CHECK: int32_t [[CONST:[^ ]*]];
+    // CHECK-NOT: [[CONST]] = 4294967292;
+    // CHECK: [[CONST]] = -4;
+    %c-4_i32 = vm.const.i32 -4 : i32
+    vm.return %c-4_i32 : i32
+  }
+}